Chart reroll mechanism



CHART REROLL MECHANISM Original Filed April 12, 1944' 4 Sheets-Sheet l INVENTOR. GEORGE W. BARNES JR ATTORNEY Nov. 15, 1949 Original Filed April 12, 1944 4 Sheets-Sheet 2 I N VEN TOR.

GEORGE w. BARNES JR.

ATTORNEY 1949 G. w. BARNES, JR 2, 87,8

CHART REROLL MECHANISM Original Filed April 12, 1944 4 Shets-Sheet 5 e2 es 97 I INVENTOR.

l v I g 1 1 l I 1 I09 BY I 1 I I l I 7| i E a i g '34 1 l b9 us n7 ATTORNEY.

1949 G. w. BARNES, JR

CHART REROLL MECHANISM Original Filed April 12, 1944 as It: a1

:5 ll: 84 Jil 17 v l 1; 2 r. i 1? E E 3 \i E 2 as as 9| B7 f @E 89 :3 a; ii 2 '1 4 Sheets-Sheet 4 IN VEN TOR.

GEORGE w. BARNES JR.

ATTORNEY Patented Nov. 15 1949 2,487,843 CHART REROLL MECHANISM George W. Barnes, Jr., Clifton Heights, Pa., as-

signor, by mesne assignments, to

Minneapolis- Honeywell Regulator Company,' Minneapolis, Minn., a corporation of Delaware Original application April 12, 1944, Serial No.

530,611. Divided and this application February 10, 1945, Serial No. 577,276

6 Claims. (Cl. 24255) The present invention relates to recording instruments, and more particularly recording instruments that are used to make simultaneously records of the values of two conditions on rec- .tangular coordinates.

This application is a division of my copend .ing application, Serial Number 530,611, filed April ment including the combination of: a supply roll on which a supply of chart paper is carried, a take-up roll for the chart paper on which a record has been made, and means for tensioning the supply roll.

Since the chart is held stationary while the record or records are made on it some means must be provided to hold it flat and taut. Means must also be provided to advance the chart to bring a new portion thereof into recording position. The used chart may either be wound into a roll to be examined later or may be torn off in sections. It is, accordingly, a specific object of the invention to provide an improved means to advance a chart to bring unused portions thereof into recording position. It is a further specific object of the invention to provide a means to maintain the chart flat and taut. while a record is being made upon it.

The various features of novelty which char- 7 acterize this invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages and specific objects obtained with its use,

reference should be had to the accompanying drawings and descriptive matter in which is illustrated and described a preferred embodiment of the invention.

In the drawings;

Figure 1 shows a front view of withthe casing door open,

Figure 2 is a back View of the mechanism supported on the chassis, Figure 3 is a top view of the chassis,

Figure 4 is a bottom view of the chassis, ,7 Figure 5 is a view of the paper feeding rolls taken on line 55 of Figure 3,

Figure 6 isa View taken on line 6-6 of Figure 5, and p a v the instrument Figure 7 is a sectional view of the chart supporting roll.

Referring first to Figure 1, there is shown an instrument casing l which is rectangular in shape and which has a door 2 mounted thereon by hinges 3. The door is shown in its open position so that the parts within the casing may be seen. The chart supporting mechanism and the recording mechanism'are both mounted on a chassis 4 that'is swingably mounted in the instrument cas ing. To this end the chassis is provided with hinge members 5 that cooperate with hinge members E3 on the casing. Hinge pins 1 extend through the members 5 and 6, so that the chassis is pivotally mounted. The chassis is held in position in the casing 2 by means of a lock 8 that is actuated by a knob 9.

The lock may be released and the chassis swung out of the case to give access to various parts of the instrument that are located on the back of the chassis, as shown in Figure 2, or to parts that maybe attached to the inside of the casing. Without going into detail, it is sufilcient to say that there are located on the chassis and in the casing two self-balancing electrical networks one of which is capable of driving a pen in a vertical direction and the other of which is capable of driving the pen in a horizontal direction across a chart in response to variations in two variable conditions. The details of the construction by means of which this may be accomplished are fully set forth in the above identified parent application, and form no part of the invention claimed herein. It can be said however, that there is provided a motor 21 which when energized serves to move the pen horizontally. There is also provided a motor 48 which when energized serves to move the pen vertically.

. As the electrical networks rebalance themselves and cause motors 21 and 48 to rotate, the pen will be moved across a chart 64 that is shown as being in strip chart form and upon which are printed a plurality of individual charts made up of rectilinear coordinates. The chart supply roll 65, as best shown in Figure 3, is mounted on one the chassis 4 while the take-up roll 66 is shown on the other side of the chassis. On its way from the supply roll to the take-up roll the chart passes a guide roll 61 which guides it across the front of a platen 68 to a guide roll 69 and a second guide roll H. Thus the chart is moved from one side of the chassis to the other across theiront of a writing platen which serves to back up the chart while a record is being made upon it.

side of The supply roll 65 is mounted upon a core which is so designed that a slight tendency to rewind the chart upon this roll is at all times present, which tendency can be overcome by the slipping of. afriction clutch. when the chart is moved. Thuseth'e chart-is at all times held under tension so that the portion thereof in front of the platen will always be taut. Figure 7, the supply roll support consists of a shaft I2 upon the upper end of whichds rotatably mounted an elongated collar 73 and upon the lower portion of which is mounted asecond collar 7 1. These collars serve to support a drum'15 that has rigidly fastened to its lower end a flange 6. The chart supply roll is mounted on the drum I5 and is kept from rotating with respect thereto by means of a spring 'I'I whose upper endis adapted to be received in the usual notch formed in the core of the chart roll. This spring is attached to the collar 13 by means of a screw 78 and its upperend extendsrthrough a notch I9 formed in the surface of the drum 15. The upper end of the shaft '12 has non-rotatably mounted on it acollan 8 I thatisprovided with an enlarged upper portionon theztop surface of which is fastened a member 82. having fiat sides. Slidably mounted on-the collar M is a. disc 83'which is pressed upwardly into engagement with the lower surface of the enlarged upper portion of the collar by means-of a spring'84t. Shaft 72 also has rotatable upon-it one member 85 of a jaw clutch that is attached-by a pin 8B.-t0 the'collar M. The member 8'5-has-a jaw 81 projecting downwardly from it which-isadapted toengage a jaw 89 projecting upwardly. from a second clutch member 88 that is-also freely rotatableupon the shaft I2. These clutch members are normally maintained in the relation shown, in which the jaws 81 and 89 do not engage each other, by means of a torsion spring 9.I- thathas one end projecting into the clutch member iii-and the other end projecting into -the clutchmember 88. Engaging the lower surface of the member 88 is a disc 92 of friction material that is pressed. upwardly into engagement: with: the member 88 by means of a disc 93 that. is-slidably received on the lower. end of the shaft 12:. The shaftat this point is provided with flats on-its-sur-face with which the disc 93 cooperates sov that it will not rotate relative thereto. Clutch member 88., disc 92,,and disc 93- are forced into engagement with. eachv other by means of spring: 9 3, whosetension can be adjusted by a nut-95f that is threadedv upon theshaft 12;

After: the. supply. roll 85" has been placed on drum I5. with-spring E1 in a notch in the roll core;. theassembly is placed: in position in the chassis (Figs. 2 and' 3) with part 82 received in a slot 8%: formed in a bracket 96 attached tothe top of the chassis. The lower end of shaft 72 is received by an opening in a bracket 98 attached to the lower endof the chassis.- The chart roll i's'maintained in the proper vertical position by a screw 99 that isthreaded into the bottom of bracket-98 to limit the dow-nward movement of shaft "I Washer 33 bearing against the lower surface of bracket 96 under the force of spring 84 assists gravity in holding the assembly in position.

In operation, as the chart is moved across the surface of the platen the chart roll will cause the drum 151to rotate with it. As the drum rotates it will-first move clutch member 85 until the jaw 8'! thereof engages the jaw 89 of clutch member 88: Thereafter, the clutch member 83 will also be moved against the friction-provided by the engagement between its lower face and the friction As shown in.

disc 92. When the chart has stopped being moved, spring Qt will tend to unwind itself to separate jaws 8'! and 89 and thereby place the chart under tension. From the above it will be seen that whenthe chart. is initially moved, the sprin 9| is placed under tension and thereafter the chart drum will be rotated against the friction of the disc Q2. When the chart is no longer moved, clutch member 88 Will remain in itsnew position and the spring 9I will place the chart under tension.

Thetake-up rolltfi (Fig. 1) is placed on a drum fill and is held in position thereon by a flange I02 on the lower end of the drum against which the roll.rests. Drum IQ-I is fastened to a shaft Ill-3 passing throng-hit, which shaft has a collar I84 rotatably mounted on its upper end. In mounting the assembly in the instrument the collar is placed in a suitable holder I05 attached to the chassis with the lower end of shaft H33 in a suitablebearing in" thezframe, Collar Iflfi' is'held in the frame. I 9.5 by'me'ans of a collar I 86 that bears against thebottomof the frame under the force ofa spring it If: desired thetake up roll can be rotated manually by means of: a knob I88, but the take-up roll. isiordinarily drivenby frictional engagement:v between its surface. and the surface of a friction driving roller: I09.

The friction drive roll I89: (Figs. 3 to 6) is rotatablysupported' in arr upper arm III and a lower .armilsi 2, whicharmsare pivotally mounted on a vertically extending shaft H3. In order that the armsmay have a goodbearing on shaft H3, each of them has a sleeve attached to it through whichthe shaft extends. One of these sleeves is shown at Hit in Figure 5 as being attached to arm H I; It is noted that guide roller 69 isalso mounted to. rotate around shaft H3 and is therefore-provided with bearings that surround the shaft, one of which is shown in Figure 5'below sleeve H41- Nor-mallythe'friction'roll I09 is spring pressed into engagement w-ith-the surface of the take-up roll 56 so thatupon rotation of the friction roll it the take-up roll will be rotated also. To this end a spring H5 is-Wrapped around the sleeve II t and has 1 one end attached thereto, while the other end bears on aportion of the chassis 4-. This-spring serves to force the arm- I I2 in a clockwise direction in-Figure3; Arm III (not shown in Fig. 4) moves'with'arm I I2. The friction drive roll Iilfi moves away from thetake-up roll 66 as the chart drawn onto-the take-up roll increases in diameter.

Aspeoialconstruction is used-on the upper and lowerendsofroll I89 to'make surethat there will' be'sufiicient friction-between that roll and the take-uproll EB-"to-drive the latter. Since the upper and lower ends of the friction driving roll are ma'deinexactlythe same manner, only the upper endthereof is shown in sectionin Figure 5. It will'be seenthat this driving roll'is mount'ed'upon sleeves II6" that are-in turn attached to a shaft Ii'I by means of a set screw H8. Th'e'shaft' II! is suitably journaled for rotation'ih arms I I I and N21 The upper end-of thesleeve Hi5 is'reduced in diameter as shown, and has placed upon it a number of friction" discs IIS that may be made of some material such as composition cork or fibre. These discs ar e tightly held in engagement with the-sleeve iIt by means of a nut IZI- that is-thread'ed upon the upper endof the'sleeve. The discs I I9 are slightlylarger'indiameter than the roller I-B9 's'o" that as the" roller is rotated; these discs will bear upon the surface of the take up take-up roll and the friction driving roll.

Rotation is imparted to the driving roll I09 by means of a gear I22 fastened to the upper end .:of the shaft I IT. This gear meshes with a pinion I I23 mounted on the arm i I I, which pinion in turn is driven by a gear IZ. As shown in Figure 5, this gear has a tubular extension that is journaled in the chassis and which is attached to a bevel pinion I25. The upper end of shaft I I3 is received by the bevel pinion which acts as a bearing therefor. The pinion I25 meshes with a second beveled pinion I26 that is attached to a shaft I21 which is journaled in bearings I28. In the operation of the device, a knob I29 on the front end of shaft I2? is rotated to rotate the pinion I26,

and the various gears forming the gear train between that pinion and gear I22, so that the .drum I99 can be rotated to drive the take-up roll.

Normally the knob IE9 is rotated in a direction so that the chart will be wound up on the roll 66. In order to prevent retrograde movement of the roll I09, the shaft I2! has mounted on it what is, in effect, a one-way brake. To this end the rear bearing 28 for the shaft I2? has in it a hard- .ened steel bushing I3I that receives the shaft.

Mounted on the outer end of the shaft is a cup shaped member I32 of such a diameter that an annular space is left between this member and bushing I3I. Within this space is a coil spring I33 that loosely encircles the bushing and which has one end attached to the cup shaped member. This spring is Wound in such a direction that upon rotation of the shaft I27 in a direction to feed the chart to roller 66, the spring will tend to expand into engagement with the inner surface of the cup member. Upon rotation of the shaft IZI'in a reverse direction, however, the spring I33 will grab the outer surface of the bushing ISI to prevent or retard rotation of the shaft I21 in that direction. From the above it will be seen that since the friction roller Iilfl cannot turn in a reverse direction, the spring Si in the supply roll can pull the chart tight without having a tendency to unwind it from the take-up roll.

At times it may be desirable to tear off each of the sections of the chart after it has had a record drawn upon it, rather than saving all of these sections in a roll. If this is the case, the chart will be directed from the guide roll I I, as seen in Figure 3, between the drum Iii! upon which the take-up roll I56 is normally mounted and the friction driving roller I09, around in front of that driving roll and behind a cutter member I34. When this type of chart drive is used, the chart is pinched between rolls Iiil and I99 to be fed forwardly below the cutting edge. When the chart has been advanced sufficiently, it may be pulled downwardly against the cutting edge to be torn off in sections. An indicator I30 on the chassis (Fig. 1) cooperates with the chart to show when it is properly positioned.

In order to simplify the attaching of the chart to the take-up roll and the threading of the chart around guide rollers 69 and I I, a means is provided to hold the friction drive roll I09 out of engagement with the take-up roll 66. For this purpose a hook I60 (Figs. 1 and 4) is fastened to the lower portion of the chassis. When a new chart is to be placed in the instrument the friction drive roll I39 is moved clockwise in Figure 4 against the force of spring H until the hook I40 is engaged behind the bent edge of the cutter bar I34. The friction drive roll will then i be held in inactive position untilit is released by removing the hook from the cutter bar.

The pen I35 which is used to make a record on the chart is mounted on a vertically movable carriage I45 that is in turn mounted on a horizontally movable frame 22I. Because of this type of mounting the pen can be moved in any direction across 'the'chart to record the varying values of thetwo conditions that are being measured.

The frame 22I carrying the pen carriage and pen is moved horizontally across the front of instrument by means of the motor 21 in response to unbalance of one of the above mentioned electrical networks. To this end, the motor 21 is attached to the lower part of the chassis 4, on the back thereof, as shown in Figures 2 and 4. As the motor rotates, it drives a pulley Ii'i through suitable gearing, including a gear I18 that is formed on the pulley. Rotation of the pulley is transferred to the frame by means of a cable I19 which has its ends wrapped around and attached to the pulley Ill. The central part of the cable extends from the low-er surface of the pulley around guide pulleys i8! and I82, the latter of which is biased in a clockwise direction in Figure 4 by a spring its (Fig. 2) in order to keep the cable under tension. Movement of the cable as the pulley I'I'I rotates is imparted to the frame due to the fact that the cable is attached to a casting IiiI of the frame 22! by means of a block I83 which grips the cable between itself and the casting. A screw I84 is provided for this purpose. 1

The pen carriage is moved vertically on frame MI by the motor 48 in response to unbalance of the other electrical network. For this purpose, the motor is mounted on the lower portion of the chassis 4 and over to one side beyond the travel of the frame. The motor drives a splined shaft ZIiii extending transversely across the lower portion of the chassis of the instrument and journaled for rotation therein. As the splined shaft 2&5 rotates, it rotates a pulley 208, as shown in Figure 4, which pulley is slidably received on the shaft 285 and is moved along the shaft as the frame moves by portions of the casting IISI which engage its sides. The pen carriage is raised and lowered by a cable 269 which has its ends fastened to pulley 298. The center portion of the cable passes over a pulley 210 as shown in Figures 1 and 3, which pulley is mounted in the upper portion of the movable frame 22 I.

From the above it will be seen that there is provided a mechanism to move a pen in two directions across a chart. There is also provided a mechanism to support a supply roll of chart and move the chart across a platen and hold it taut in recording position. The chart may be either rerolled. or torn 011 in sections, as desired.

While in accordance with the provisions of the statutes, I have illustrated and described the best form of this invention now known to me, it would be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of this invention as set forth in the appended claims, and that in some cases certain features of this invention may sometimes be used to advantage without a corresponding use of other features.

Having now described this invention, what I claim as new and desire to secure by Lettersfirst. roller mounted for" rotation around a fixed axis, a frame; asecondroller'mounted:for rotation insaidframe,.means to mount said frame for swinging movement, means tobias said frame in. a direction to bring saidsecond roller into ed" on said frame, meansto bias said frame in a direction to bring said driving drum. into frictional engagement with the periphery of the take-up roll on said supporting means, meansto rotate said driving drum in a direction to pull the chart onto the take-up roll, and means to preventreverse rotation of said driving drum,

3; In a recording instrument having a chart upon which a record is to be made, a backing surface over which the chart is drawn, a guide roll around which the chart passes as it moves across said surface, a rotatable drum upon which said chart is to be wound, a friction driving member to engage said drum and wind the chart thereon, means to support said driving member for pivotal movement around said guide roll so that it may move" away from said drum as the chart thereon increases in diameter, means to biasJsaid driving member around its axis toward said drum, and means to rotate positively said driving member.

4. In a recording instrument having a chart upon which a record is to be made; a backing surface over which the chart is drawn; a. supply roll for said chart, means tendingto. rotate said supplyroll ina reverse direction at all times to maintain said chart under tension, a chart takeup roll, a positively driven member, means to mount. said member for pivotal movementtoward and from said take-up roll whereby saidmember can engage the surface of said take-up roll to wind chart thereon, and a'guide roll located coaxially'with the'pivot around which the means to mount said member moves.

5'; Ina recordinginstrument having a chart upon :wh'i'c'ha record is to bemade, means. to hold a supply roll of. chart, means to hold a take-up roll of. chart; means. to apply a reverse pull to said: supply roll: at. all times to maintain the chart between. the supply and take-up rolls taut, meansto wind charti on said take-up rollincluding a pivoted frame; a friction drive roller on said frame, means to bias said frame in a direction to force said drive roller against said take-up roller to'rotate. the latter and wind chart thereon, andiazcutter bar'carried by said frame adjacent said drive roller whereby chart fed betweensaid drive roller and take-up roll may be torn when it has been drawn between said roll and roller.

6; In a recording instrument having a chart upon which a record is to be made, means to draw the chart pasta recording station comprising-alr'otatable member upon which the chart is to be rolled, means to support said member for rotation around a fixed axis, a friction drive roller to engage the'chart on said member, means to mount said roller for movement around an' axis toward andaway from said member, means to biasiresiliently said means to mount said roller in a direction to move said roller toward said member and the chart wrapped thereon, means to rotate. said roller around it's own axis including a shaft concentric with the axis around which said means to mount said roller ismoved, drive means between said shaft and said roller, and means cooperating with said drive means to prevent reverse movement of said drive means and friction drive roller.

GEORGE W. BARNES, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 877,232 Rolland Jan. 21, 1908 1,691,414. Thornton Nov. 13, 1928 1,815,681 Schellentrager July 21, 1931 1,831,790 Leong Nov. 10, 1931 1,953,869 Sadgebury Apr, 3, 1934 2,034,543 Twiss et all Mar. 17, 1936 2,321,273 Belcher June 8, 1943 

